For 35 minutes on February 21st, air traffic controllers at Cleveland Hopkins International Airport could not talk to pilots trying to land or take off at the airport. Wires connecting the tower were hit by construction crews working... (www.cleveland.com) Plus d'info...

Flights were delayed 2 hours but by 11AM the SCHEDULE was back on track

Planes that had already descended and that their pilots could see the field could have landed without communicating with the tower.

Seems to me back in flying 101 that if you were in CONTROLLED AIRSPACE that you had to communicate with whomever was controlling it. Has everyone forgotten about that light that hangs down there in the the tower cab. Last I heard, it wasn't for decoration but just exactly for times like these or the tower being able to contact sombody by radio.